Method for storage management of storage resource on a storage network

ABSTRACT

A storage resource operation managing method in a storage network arranged by a node for transmitting an access request via a network to a storage and by a plurality of storage groups which receive the access request so as to execute a content of the access request includes the following steps, a logical distance defined from the node to the storage resource is acquired, alternatively, geographical distances among the respective storage resources are acquired, alternatively, in such a case that both the logical distance and the geographical distance are acquired, requests with respect to the respective distances are acquired, and a storage resource is selected, an acquired requirement range is entered into a selection factor so as to select a desirable storage resource.

BACKGROUND OF THE INVENTION

The present invention generally relates an operation managementtechnique of an SSP (Storage Service Provider) which owns a storagenetwork, namely a SAN (Storage Area Network) and a plurality of NASs(Network Attached Storages), and provides a storage region (storageresource) to a client, while the storage network is constituted bycoupling a plurality of storages with a plurality of servers in a highspeed. More specifically, the present invention relates to a storageresource selection technique, a disaster recovery technique, and a costreduction technique, which are met with requirements of clients underoptimum condition.

Conventionally, storage devices have been used as appendix articles,namely external storage units of servers such as disk devices and tapeapparatus. However, in connection with importance of information as wellas extensions of storage capacities, data exchanges and data sharing arerequired among a plurality of systems. As a result, NASs (NetworkAttached Storages) having large capacity storages, a common carrierleased network which couples a storage group to a server group in a highspeed, and SANs (Storage Area Networks) have been popularized. In suchan SAN, storage consolidation is realized by employing a server groupand a storage group, so that higher efficiencies of system operation maybe realized.

Generally, a storage administrator within an enterprise uses amanagement tool in order to manage topology of an SAN, and also tooperate/manage connections between NAS appliances and a server.

In accordance with a management tool, various information such ascapacities, empty capacities, and network topology related to storagesand servers are acquired, and then servers, storages, and networkappliances, which are connected to an SAN are displayed on a displayscreen. Since icons related to the respective appliances are clicked onthe screen, more detailed information (for example, capacities ofrespective storages and states of storage assignment to servers) can bedisplayed on the display screen. Then, not only the managementinformation is acquired/displayed, but also storages and logical areaswithin storages are allocated to the server, and these allocations aredeleted, or changed. Also, since back-up setting operation/back-up toolare combined with the above-described management tool, utilization of asystem may be effectively increased.

However, storage operation administrators employed in enterprises arefacing to various problems, for instance, increases of cost with respectto increases of storages which are not predictable in recent years,complex structures of management tools in various fields, space savingaspects of installation spaces for storages. These problems may besolved in such a manner that while information resources owned withinenterprises are transferred in an outsourcing manner to such anenterprise which exclusively operates/manages storages, all of storageoperations/managements are consigned to an external enterprise. As suchan enterprise which operates/manages storages and lends storageresources to clients, an SSP (Storage Service Provider) is known (see“Data Storage Report 2000” of Japanese monthly magazine “Computopia”, onpages 36 to 37).

FIG. 13 is a network structural diagram for indicating operation modesof an SSP (Storage Service Provider) 103.

A client who wants to consign information resources provided within theown enterprise (firm) in an outsourcing manner installs a customer'sserver 108 corresponding to the server of the own firm within the SSP103, and accesses from a customer's console 100 installed in the ownfirm to the customer's server 108 of the own firm. The SSP 103 isconstituted by a storage device (106, 107), an SAN 105, and a customer'sserver group (108, 109, 110). All of nodes which are connected to theSAN 105 are managed by a management server 104. The SAN 105 is arrangedby a fiber channel, the Ethernet, or the like. Both the customer'sconsole 100 and the customer's server 108 corresponding to the server ofthe own firm are connected to each other by way of either an NFS(Network File System) or a CIFS (Common Internet File System), or by wayof a common carrier leased line, while using a VPN (Virtual PrivateNetwork) 101 on the Internet 102. The customer's console 100 isconnected via the Internet 102 to the management server 104.

In the SSP 103, in such a case that a storage area allocation request isissued from the client via the customer's console 100, the SSP 103interrogates access performance, reliability, usage, and the like, whichcorrespond to the request of the client with respect to the storage,from the customer's console 100, and then selects such a storageresource which is fitted to the request. When the storage resource isselected, the SSP 103 uses a management tool. The management toolcontinuously acquires from the storage, a value indicative of a state ofa storage resource (will be referred to as “resource state information”hereinafter), while this resource state information corresponds to anoperation state of a storage resource, a use condition thereof, and athroughput thereof. While the above-described resource state informationis used as a selection factor, the SSP 103 selects such a storageresource fitted to the request of the client 100 from the resource stateinformation.

Next, the SSP 103 assigns the selected storage resource to thecustomer's server 108. In order to assign a storage resource to theserver 108, the previously existing SAN topology management tool, and avolume management tool contained in a storage may be used. Since theabove-described storage resource is assigned, the customer's console 100may use the storage resource which satisfies the performance request inthe customer's server 108. Also, information saved in the customer'sserver 108 may be viewed, set, and changed from the customer's console100.

FIG. 14 is a flow chart for describing a process operation of a storageresource assignment to the customer's server 108.

In this flow chart, the SSP 103 has continuously acquired resource stateinformation 200 contained in the storage, such as an operation ratio, aload ratio, an empty storage, an RAID level, DISK performance, and thelike as to the storage (step 201). Under this condition, in such a casethat the SSP 103 receives both a rental request of a storage region, anda request 202 related to a capacity and performance with respect to astorage resource from the customer's console 100 (step 203), this SSP103 selects such storage resource which is fitted to the request of theclient, while using the previously-acquired resource state information200 as a selection factor (step 204). Then, the SSP 103 assigns theselected storage to the customer's server 108 (step 205). To assign thisselected storage resource, the presently-existing SAN topologymanagement tool, or the assignment tool for the volume within thestorage is used. The SSP 103 notifies such a fact that the storageresource is usable via the management server 104 to the customer'sconsole 100 (step 206).

Also, the SSP 103 copies necessary data as back-up data with respect tothe storage resource used by the customer's server 108 in order torecover the necessary data when a trouble happens to occur. In thiscase, in order that the back-up data is not deleted at the same time dueto the occurrence of trouble, while another storage device differentfrom the storage device used by the client is secured, the SSP 103copies the data stored in the storage resource.

In the above-described prior art, the following mode is represented.That is, while the SSP 103 owns the servers 108, 109, 110 of the clientswithin the SSP 103, the SSP 103 causes the customer's servers to use theSAN 105. However, there is another mode. That is, in the SSP 103, anetwork is connected from the SAN 105 provided in the SSP 103 isdirectly connected to a customer's firm, so that the SSP 103 may providea storage service. In this alternative case, the customer's server 108shown in FIG. 1 may become a network structure which is located at theplace of the customer's console indicated in FIG. 13.

As previously described, in the prior art, either the management tool orthe storage administrator selects such a storage resource which isfitted to both the capacity and the performance requested by the clientbased upon the resource state information of the storage resource, andthus, may realize the assignment of the selected storage resource to thecustomer's server. Also, since the data stored in the storage resourceare copied as the back-up data, the high utility of the SSP may bemaintained.

In the conventional technique, while resource state information(operation condition, capacity, use condition, throughput and the likeas to storage resource) within each of storages, which is obtained fromthe management tool, is used as a selection factor, such a storageresource is selected and allocated to a client, which can satisfy both acapacity and access performance of a storage requested by this client.

However, in such an SSP which may unitedly provide resources and NASs onan SAN, distributed in long distances, to a client by using a wide areanetwork (WAN), a large number of composite networks are used in the SSP.In such a network, network access time between the storage resource andthe customer's server may give an influence to access performance to astorage. As a result, only such resource state information (operationratio, disk performance, and the like) corresponding to a factor fordetermining access performance within the storage resource can hardlysatisfy entire access performance which is required by the client.

Furthermore, in the case that while storages which are broadened anddistributed over long distances are effectively utilized, and alsoback-up operation capable of solving disaster problems such as anearthquake is carried out, positional information such as installationareas of storage units is not acquired in the presently availablemanagement tool. As a consequence, this presently available managementtool owns no means capable of intentionally selecting storage unitswhich are located far from a designated distance.

Also, in the case that a client which utilizes an SSP moves, sincenetwork access time required from a move destination to a storageresource is not considered, there are some possibilities that data istransferred to such a storage located near the move destination of thecustomer's server. Under such a circumstance, work cost required totransfer the above described data is necessarily required every time theclient moves.

SUMMARY OF THE INVENTION

An object of the present invention is given as follows: That is, in astorage management system capable of providing a storage resource to aclient, a selection is made of such a storage resource which can satisfynot only storage resource performance, but also network accessperformance defined from a node used by the client up to the storageresource in response to a request issued from the client.

Then, this object of the present invention is to provide such a storageresource operation managing method capable of providing to the client,an optimum storage resource which is fitted to the request of theclient. It should be understood that information such as a total hopcount, packet response time, and a network throughput, which is relatedto network access performance from a node to a storage resource, networkaccess performance between storage resources, or network accessperformance between nodes will be referred to as a “logical distance”hereinafter. This total hop count corresponds to a number for indicatinghow many stages of routers are used in a communication.

Another object of the present invention is to provide adisaster-resistant performance improving method used when regionaldisaster such as an earthquake happens to occur in such a manner that aplurality of storage resources which are separated far from anintentionally set distance are selected from storage resourcesdistributed in a broad area, and then, the selected storage resourcesare copied in a back-up manner.

A further object of the present invention is to provide a method ofreducing work cost related to movement of a storage resource and/or datastored in a storage resource as follows: That is, in such a case that ageographical distance between a node accessed to a storage resource andthis storage resource is changed, if a logical distance defined from thenode up to the storage resource after the geographical distance haschanged can satisfy a request of a client with respect to accessperformance, then movement of the storage resource is not carried out,or movement of the data stored in the storage resource is not carriedout.

In order to achieve the above-described objects, the present inventionmay provide such a method for managing storage resources, while usingboth information related to network access performance defined from anode which uses a storage resource up to this storage resource, andinformation related to a geographical location relationship between theabove-described node and storage resource, and also among the respectivestorage resources. The first-mentioned network access performanceinformation will be referred to as a “logical distance” hereinafter,whereas the last-mentioned geographical location positional relationshipinformation will be referred to as a “geographical distance”hereinafter. Also, according to the present invention, both adisaster-resistant performance improving method and a work cost reducingmethod may be provided.

Concretely, the below-mentioned methods (1) to (7) may be provided.

(1) Storage Resource Operation Managing Method:

A network is arranged by a node for transmitting an access request viathe network to a storage, and also, a plurality of storage groups whichreceive the access request to execute this received access request.

In this network structure, any one of a logical distance and ageographical distance is acquired, or both the logical distance and thegeographical distance are acquired. The logical distance is definedbetween the above-described node and a storage resource contained in thestorage group, or between the respective storage resources contained inthe storage resource groups. The geographical distance is definedbetween the node and the storage resource, or between the respectivestorage resources contained in the storage resource groups. Furthermore,while a request with respect to the acquired distances is acquired, arequirement range is set as a selection factor used when a storageresource is selected.

In accordance with this managing method, while not only performance ofthe storage resource itself, but also the logical distance defined fromthe node used to access the storage up to the storage resource, andfurther, the geographical distance between the storages are considered,the desirable storage resource can be selected from the storage networkdistributed, or spread in a wide ares. As a consequence, such a storageresource operation managing method can be provided by which an optimumstorage resource can be provided to the clients which utilize thestorages.

(2) Method of Selecting Optimum Storage Resource:

In the above-described managing method (1), either the logical distanceor the geographical distance is acquired. Otherwise, both the logicaldistance and the geographical distance are acquired. Furthermore, whilethe request for the acquired distances is acquired, the requirementrange is set as the selecting condition of the storage resource. Then,such a storage resource whose logical distance is located within therequirement range is selected. Alternatively, another storage resourcewhose geographical distance is located within the requirement range isselected. Otherwise, such a storage resource whose logical distance andgeographical distance are located within the requirement range isselected.

(3) Method of Selecting Optimum Storage Resource:

In such a case that there are plural storage resources which areinstalled within the requirement range shown in the above-explainedselecting method (2) in accordance with this selecting method (2), afurther optimum storage resource is selected by using the followingconditions, namely, a storage resource whose logical distance is theshortest distance; a storage resource whose geographical distance is theshortest distance; a storage resource whose geographical distance is thelongest distance; a storage resource whose logical distance andgeographical distance are either the shortest distances, or the longestdistances; or any one of these selecting conditions among the storageresources located within the requirement range.

(4) Method of Selecting Optimum Storage Resource:

In such a case that such a storage resource cannot be found out which isinstalled within the requirement range shown in the above-describedselecting method (2) in accordance with this selecting method (2), anoptimum storage resource is selected from all of storage resources,while using the following selecting conditions, namely, the storageresource whose logical distance in the above selecting method (2) is theshortest distance; the storage resource whose geographical distance inthe above selecting method (2) is the shortest distance; the storageresource whose geographical distance in the above selecting method (2)is the longest distance; the storage resource whose logical distance andgeographical distance in the above selecting method (2) are either thelongest distances or the shortest distances; or any one of theseselecting conditions.

(5) Method of Forming Optimum Storage Resource:

In such a case that such a storage resource cannot be found out which isinstalled within the requirement range shown in the above selectingmethod (2) in accordance with this selecting method (2), such a storageresource whose logical distance shown in the above selecting method (2)is located within the requirement range is newly added; such a storageresource whose geographical distance shown in the above selecting method(2) is located within the requirement range is newly added; or such astorage resource whose logical distance and geographical distance arelocated within the requirement range of the above method selecting (2)is newly added.

Similar to the above-explained managing method (1), in accordance withthe above-described selecting/forming methods (2) to (5), such a storageresource operation managing method can be provided by which the optimumstorage resource can be provided to such a node indicative of therequest with respect to the storage resource.

(6) Disaster-Resistant Performance Improving Method:

With respect to such a storage resource located in the network shown inthe above managing method (1), a requirement range as to a geographicaldistance thereof is acquired in accordance with the method shown in theabove-described selecting method (2) (this storage resource will bereferred to as a “primary resource” hereinafter). Then, another storageresource (will be called as a “secondary resource” hereinafter) isselected which is installed in the set requirement range and isdifferent from the primary resource. Either a data portion or all of thedata stored in the primary resource is duplicated, and then, theduplicated data is stored into the secondary resource. Then, in such acase that the primary resource cannot be used due to an occurrence of acertain trouble, the access request which is issued from the node fortransmitting the access request with respect to the primary resource isexecuted in the secondary resource.

In accordance with this disaster-resistant performance improving method,the data stored in the storage resource can be saved in the back-upmanner at a position which is intentionally separated far from thepresent position thereof. As a consequence, the data stored in thestorage resource can be maintained with respect to such disaster whichlocally happens to occur, and therefore, disaster recovery operation canbe realized.

(7) Cost Reducing Method:

With respect to both a node and a storage resource, which are locatedwithin the network shown in the above-described managing method (1), arequest for a logical distance is acquired based upon the selectingmethod indicated in the above selecting method (2). In the case that ageographical location of this node is moved, a judgement is made as towhether or not a logical distance defined from this node up to thestorage resource is located within the acquired requirement range evenafter this geographical location has been moved. When the logicaldistance is located within the requirement range, movement of thestorage position of the data within the storage resource is not carriedout.

In accordance with this cost reducing method, in such a case that aserver of a customer which uses a storage is moved, for instance, thisserver positionally moves, it is possible to check as to whether or notnetwork access performance defined from the server up to a storageresource achieved after this server has moved is changed, as comparedwith such network access performance achieved before this server moves.Then, when the network access performance is located within such aperformance range requested by the client, it is possible to judge thatmovement of data is not required. As a consequence, such cost requiredin data movement can be reduced in the storage resource operationmanagement.

BRIEF DESCRIPTION OF THE DRAWINGS

For a better understanding of the present invention, reference is madeof a detailed description in conjunction with the accompanying drawings,in which:

FIG. 1 is a network structural diagram for indicating an operation modeof an SSP 302 to which a first embodiment mode of the present inventionis applied;

FIG. 2A and FIG. 2B are diagrams for schematically representing acustomer's console 300 and a customer's server 304;

FIG. 3 is a diagram for schematically showing a management server 303;

FIG. 4 is a diagram for representing a storage resource informationtable contained in a database 501 formed in the management server 303;

FIG. 5 is a flow chart for explaining operations executed in the casethat a storage resource assignment is performed by a storage managementprogram 502;

FIG. 6 is a flow chart for describing operations of network logicaldistance acquisition by a network logical distance acquisition program402;

FIG. 7 is a flow chart for explaining storage resource selectingoperation by a storage management program 502;

FIG. 8 is a flow chart for describing both back-up resource selectingoperation and back-up setting operation by the storage managementprogram 502;

FIG. 9 is a flow chart for explaining operations by the storagemanagement program 502 when a trouble happens to occur;

FIG. 10 is a network structural diagram for representing a relationshipbetween SSPs (A, B) and a customer's server 1300, to which a secondembodiment mode of the present invention is applied;

FIG. 11 is a network structural diagram in the case that the customer'sserver is moved from the network structure of FIG. 10 to which thesecond embodiment mode is applied;

FIG. 12 is a flow chart for describing operation for judging as towhether or not the storage resource of the storage management program502 must be moved;

FIG. 13 is the network structural diagram for indicating the operationmode of the conventional SSP 102; and

FIG. 14 is the flow chart for explaining the storage resource assignmentexecuted by the storage management program in the prior art.

DESCRIPTION OF THE EMBODIMENTS

Now, a description is made of a first embodiment mode of the presentinvention.

FIG. 1 is a network structural diagram for indicating an operation modeof an SSP 302 to which a first embodiment mode of the present inventionis applied.

In this network structure, a console 300 indicates a console node of aclient to which an information resource contained in an enterprise isconsigned in an outsourcing manner. The client installs a customer'sserver 304 corresponding to a server of the own enterprise (firm) withinthe SSP 302, and this client sets/changes an application program storedin the customer's server 304, and acquires information from the console300. The console 300 installed within the client's firm may access thecustomer's server 304 connected to the SSP 302 via the Internet 301 on anetwork connected to a VPN (Virtual Private Network) by way of an NFS(Network File System).

The SSP 302 is constituted by a management server 303, the customer'sserver 304, storage units 306 and 307, and also a router 305. Themanagement server 303, the customer's server 304, the storage unit 306,and the router 305 are connected to each other in a LAN (Local AreaNetwork) manner by using an Ethernet 308. Also, the storage unit 307 isconnected to the router 305 in a LAN manner by employing anotherEthernet 309. Routing operation is carried out between the LAN 308 andthe LAN 309 by the router 305. In the network structure of FIG. 1, theLAN connections among the storage units 306/307, the management server303, and the customer's server 304 are established by employing theEthernet and the router. However, this connection method is not limitedonly to this network structure. Alternatively, while the storage unitsare connected to customer's servers by employing fiber channels and thelike, these fiber channels may be connected to each other by using fiberchannel switches. Also, according to the present invention, there is nolimitation in total numbers as to all of these console, customer'sserver, management server, router, and storage units. Also, there is nolimitation in total stages as to these routers. Further, the networktopology between the console 300 and the nodes within the SSP 302 is notlimited only to the Internet, but may be established by either a commoncarrier leased line or an ATM.

In the above-described network structure, in the case that the clientissues an assignment request for a logical area within a storage unit tothe management server 303 of these SSP 302 by using the console 300, themanagement server 303 selects such a logical area which is fitted to therequest of the client as to the storage area, and then assigns, orallocates the selected logical area to the customer's server 304. Inthis first embodiment, it should be understood that the above-describedstorage units, a geographically-divided area within the storage unit, alogically-divided area within the storage unit, and a logically-dividedarea which is formed over a plurality of storage units will be referredto as a “storage resource.” After the management server 303 allocates astorage resource, this management sever 303 notifies an address of thecustomer's server 304 to the console 300 so as to establish both anaccess operation from the console 300 to the customer's server 304, andanother access operation from the customer's server 304 to the storageresource.

Subsequently, the console 300, the customer's server 304, and themanagement sever 303 will be successively explained with reference toFIG. 2A, FIG. 2B, FIG. 3, and FIG. 4.

FIG. 2A and FIG. 2B are structural diagrams for illustratively showingboth the console 300 and the customer's server 304. The console 300accesses the WWW server on the Internet, while a request transmissionprogram (Web browser) 400. Also, the console 300 may access thecustomer's server 304 by using the NFS. In the request transmissionprogram (Web browser) 400, the console 300 accesses both a clientpositional information input page and a storage resource selectioncondition input page on the management server 303 so as to perform inputsetting operations, respectively. Also, while the console 300 accesses astorage state display page, this console 300 may view resource stateinformation such as a capacity, a use ratio, and a throughput as to astorage resource allocated to the customer's server 304. Further, theconsole 300 may view such information related to a logical distance, anda geographical positional information which may be expressed by latitudeand longitude of an installation place. This logical distancecorresponds to response time of a packet, and a total hop countindicative of a total stage number of routers through which a packet istransferred.

In the customer's server 304, while a logical distance acquisitionprogram 401 is operated, a Ping program corresponding to a networkdiagnostic program is executed in a periodic manner with respect to allof the storage units, so that packet response time to the storageresource is measured from a response packet. At this time, a total hopcount between the customer's server 304 and the storage resource isacquired, and then, both the measured packet response time and theacquired hop count are notified as a logical distance to the managementserver 303.

FIG. 3 is a schematic diagram for showing an internal arrangement of themanagement server 303. The management server 303 is arranged by a clientrequest reception program (WWW server) 500, a database 501, and astorage management program 502.

The client request reception program 500 corresponds to a WWW server,and transmits a client positional information input page, a storageresource selection condition input page, and a storage state displaypage to the Web browser. In the client request reception program 500,since a Web page is inputted from the console 300, both a storageresource selection condition and client positional information (latitudeand longitude) are acquired.

The storage management program 502 is arranged by a network topologysearching/acquiring module 503, a back-up setting module 504, a storageresource allocating module 505, a node positional information acquiringmodule 506, a storage resource selecting module 507, and a GUI module508. Both the back-up setting module 504 and the storage resourceallocating module 505 are operable in accordance with the existingtechnique.

In the network topology searching/acquiring module 503, informationrelated to electronic appliances which are connected to the storagenetworks 308 and 309 provided in the SSP 302 is acquired to be stored inthe database 501. Furthermore, another information which is acquired bythe logical distance acquisition program 401 operated on the customer'sserver 304 is also stored into the database 501. In the node positionalinformation acquiring module 506, an installation position (latitude andlongitude) of each of the detected storage is acquired via the GUImodule 508 so as to calculate a geographical distance. Then, thecalculated geographical distance is stored into the database 501. In thestorage resource selecting module 508, such a storage resource which maybe fitted to both a required capacity and required performance by aclient with respect to a storage resource is retrieved, or searched fromthe database 501 to be selected. In the GUI module 508, while thestorage server and the customer's server, which are acquired by thenetwork topology searching/acquiring module 503, are displayed on thedisplay screen, the installation positions, the latitude, and thelongitude of the respective nodes are manually inputted from anadministrator of the SSP 302.

FIG. 4 is a diagrammatic diagram for showing a storage resourceinformation table 600 related to storage resources stored in thedatabase 501. The storage resource information table 600 containsthereinto a storage name/LUN 601, an averaged operation ratio (%) 602, acapacity (GB) 603, a rotation per minute (rpm) 604 indicative of diskperformance, access time (msec) 605 within the disk, packet responsetime (msec) 606 from a customer's server, an installation place (northlatitude, east longitude, location name) of a storage unit, a logicaldistance (Km) 608 from a customer's server, and a total hop count(stage) 609 between a customer's server and a storage unit. As to thisstorage resource information table, one information table is formedevery customer's server. The storage resource information table 600 isused as a selection factor when a storage resource is selected.

Referring now to FIG. 5, FIG. 7, and FIG. 8, a description is made ofstorage resource allocation (assignment) operation flows of the storagemanagement program 502 stored in the management server 303 shown in FIG.2A and FIG. 2B. An acquisition operation flow of a logical distancedefined from a customer's server to a storage resource will now bedescribed with reference to FIG. 6. FIG. 9 is a flow chart fordescribing operation flows of the storage management program 502 when atrouble happens to occur in a storage resource.

FIG. 5 shows a storage resource allocation operation flow of the storagemanagement program 502. The storage management program 502 searches, orretrieves network topology with respect to the storage network of theSSP 302 (step 700), while using the network topology searching/acquiringmodule 503, and stores the information related to the network structureinto the database 501. Also, the storage management program 502 acquiresresource state information 700 such as an operation ratio, a capacity, adisk rotation per minute, and access time within a disk with respect tothe found storage resource, and then, stores the acquired resource stateinformation 700 into the information table 600 contained in the database501 (step 701).

Next, in the node positional information acquisition module 506, bothlatitude and longitude (geographical distance) are acquired whichindicate a geographical place of the storage resource. Both the latitudeand the longitude are entered by the administrator of the SSP 302 byemploying the GUI module 508. The node positional informationacquisition module 506 calculates geographical distances among all ofthe storage resources, and then stores the calculated geographicaldistances into the storage resource information table 600. Furthermore,the node positional information acquisition module 506 acquires bothpacket response time and a total hop count (namely, logical distance)702 defined between the customer's server 304 and the storage resourcefrom the logical distance acquisition program 401 operable on thecustomer's server 304, and then, stores the acquired packet responsetime and total hop number into the storage resource information 600(step 703).

Then, the above-described data acquisition operation defined in the step703 is repeatedly carried out every time a constant internal has passed.A flow operation of acquiring a logical distance in the customer'sserver 304 will be explained later with reference to FIG. 6. Under theabove-explained condition, while the client request reception program500 is executed, the node positional information acquisition module 506receives a notification 704 for requesting a storage resource assignmentissued from a client, and both a required storage capacity 705 andanother request with respect to a logical distance defined from thecustomer's server 304 to the storage resource (step 706). This logicaldistance corresponds to packet response time, a total hop number, anetwork throughput, and the like.

In this first embodiment mode, information related to theabove-explained data access performance will be referred to as a“logical distance.” Such a fact that a logical distance is short mayindicate such a condition that time required for data access operationis short, for instance, packet response time is short, a total hop countis small, and a network throughput is high.

A requirement rage 705 in this first embodiment is assumed in that atotal hop count is minimum. The storage resource selection module 507retrieves such a storage resource which is fitted to both therequirement range and the required capacity 705 from the resource stateinformation which has been stored in the database 501, the logicaldistance, and the geographical distance, and then selects a properstorage resource (step 707). In this first embodiment, an actualdistance obtained from a geographical location information will bereferred to as a “geographical distance.” Furthermore, such a storageresource selected at the step 707 will be called as a primary resource.A storage resource selection flow operation defined in the step 707 willbe explained later in detail with reference to FIG. 7.

FIG. 6 is a flow chart of explaining a logical distance informationacquisition flow operation by the logical distance acquisition program401 executed on the customer's server 304. In the logical distanceacquisition program 401, when the logical distance is acquired in thestep 703 of FIG. 5, both the packet response time and the total hopcount are acquired to be provided to the storage management program 502.

In the logical distance acquisition program 402 executed on thecustomer's server 304, a Ping program is executed from the customer'sserver with respect to each of these storage resources so as to acquireboth packet response time and a total hop count corresponding to a totaltime of the customer's server which passes over segments. The Pingprogram originally corresponds to a network diagnostic program capableof diagnosing a network as follows: While data having a constant bytenumber is transmitted plural times to a designated node, a check is madeas to whether or not a response is returned from a node to which data istransmitted in order to diagnose the network.

In order to avoid that a packet present on a network is continuouslytransmitted, a TTL (Time To live) value indicative of an expiration termis contained in the packet present on the network. This TTL manner is asfollows. While a TTL is set when a packet is transmitted, the value ofthis TTL is subtracted by 1 every time the packet passes through arouter, and then, when the value of this TTL becomes 0, this packet isdiscarded.

A TTL value when a response is firstly obtained may indicate a totalstage number of routers up to a target node, namely, a total hop countby using this TTL manner in such a manner that while the TTL value issequentially increased from 0, a Ping program is executed with respectto the target node. Also, in the Ping program, since data transmissionoperation is carried out plural times, an average value of packetresponse time of the respective packets may be acquired. At a firststage, while a TTL value of a storage resource is set to 0, a Pingprogram is executed (step 800).

A check is made as to whether or not a response by executing the Pingprogram is received (step S801). When the response is not obtained, theTTL value is increased by 1, and then, the Ping program is againexecuted (step 802). A series of this process operation is carried outwith respect to all of the storage resources. When the response isobtained by executing the Ping program, a total hop count between acustomer's server and a storage resource based upon the TTL value (step803). At the same time, packet response time is required (step 804), andthen, both this packet response time and the total hop count arenotified to the management server 303.

FIG. 7 is a flow chart for explaining flow operation defined at theprimary resource selection step 707 of FIG. 5. In this embodiment, arequest of the console 300 is to select such a storage resource, thetotal hop count of which is the smallest count (step 705 shown in FIG.5). To this end, the content of the database 501 is retrieved so as tosearch such a storage resource whose total hop count is equal to 0,namely, a storage resource which is located at the same segment with thecustomer's server 404 (step 900). In the case that such a storageresource cannot be found out (step 900), the hop count is increased by 1stage (step 904). Then, a judgement is made as to whether or not thereis a storage resource located far from the increased hop count (step905).

In such a case that the storage resource is present at a segmentdestination via a designated hop count, or another segment far from thissegment destination (step 905), a search is again made as to whether ornot a storage resource is present at a segment succeeding to adesignated stage number in the step 901. When the storage resource ispresent at the designated segment in the step 901, a search is made asto whether or not such a storage resource having a capacity larger than,or equal to a capacity required by the client 400 at the segment of theselected hop count (step 902). If such a storage resource cannot befount out, then a total hop count is increased and then, the searchingoperation is again performed (step 904). In the step 902, when thestorage resources having the capacities larger than, or equal to therequired capacity can be found out, such a storage resource among thesefounded storage resources is selected as the storage resource for theclient 400, namely, selected as the primary resource (step 903). Thatis, this selected storage resource implies that a summation thereofbetween the average access time within the disk and the packet responsetime of the Ping program is the fastest time.

In such a case that the storage resource having the capacity largerthan, or equal to the target capacity cannot be found out within the SSP302 in the step 905, such a storage source having a capacity largerthan, or equal to the capacity required by the client is formed withinthe segment whose hop count is “0” from the customer's server (step906). Then, the formed storage resource is selected as the primaryresource (step 907).

FIG. 8 is a flow chart for explaining flow operations defined in thestep 709 for selecting the backup resource and for setting the regularback-up operation. In this flow operation, when the primary sourcemalfunctions due to an occurrence of disaster such as an earthquake, theback-up setting operation is carried out in order that data stored in aresource can be recovered.

In this flow operation, first of all, a sufficiently long distance bywhich disaster does not give an adverse influence to both a back-upresource and a primary resource is acquired as a requirement range of ageographical distance (step 1000). It should be understood that asufficiently long distance by which disaster never gives an adverseinfluence will be referred to as a safety distance. Next, such a storageresource having a storage capacity larger than that of a primaryresource is retrieved from storage resources except for the primaryresource (step 1001). In the case that the above-described storageresource is present (step 1002), another storage resource having acapacity equal to the capacity of the primary resource is formed at aplace which is separated from the primary storage by a distance longerthan, or equal to the safety distance, and is installed at this place(step 1008).

In the case that the storage resources having the capacities largerthan, or equal to the capacity of the primary resource can be found outin the step 1002, a search operation is made as to whether or not thereis such a storage resource present at a place located far from thesafety distance among the founded storage resources from the storageresource retrieve table 600 (step 1003). To the contrary, in the casethat the above-described storage resource cannot be found out, a newstorage resource is formed in a similar manner to such a case that thestorage resource having the same capacity as the capacity of the primarystorage. Then, this newly formed storage resource is installed at aposition separated far from the primary resource by a distance longerthan the safety distance (step 1008).

Then, next, either in such a case that the storage resource is presentat such a place separated from a distance longer than, or equal to thesafety distance in the above described step 1004, or in the case thatthe storage resource is newly formed in the step 1008, such a storageresource is selected as a back-up resource, the summation of which isthe fastest. This summation is calculated between the packet responsetime of the Ping program from the customer's server 304 and the diskaccess time of the storage (step 1005).

The selected back-up resource is set as a back-up purpose storage in theback-up setting unit 504 (step 1006). Then, such a setting operation iscarried out in a step 1007. That is, the data stored in the primaryresource is copied to the back-up resource at a predetermined timeinstant (for example, 0:00 AM every day).

FIG. 9 is a flow chart for describing flow operations of the storagemanagement program 502 in the case that a trouble happens to occur in astorage resource. The storage management program 502 regularly executesthe process operation of the step 701 shown in FIG. 5 (namely, retrieveof network structure and acquisition of resource state information) withrespect to all of the storage resources even after a series of storageresource assignment process operation has been completed (step 1100). Atthis time, a check is made as to whether or not there is such a storageresource having no response with respect to the retrieve of the networkstructure and the request of the resource state information acquisition(step 1101). When there is no such a storage resource, namely theresponses are issued from all of the storage resources, theabove-explained process operation defined in the step 1100 is repeatedlycarried out.

In the case that there is such a storage resource having no response dueto a certain trouble in the step 1101, a judgement is made as to whetheror not this storage resource corresponds to the primary resource (step1102). When it is so judged that the storage resource judged in the step1102 is not equal to the primary resource, another judgement is made asto whether or not this judged storage resource corresponds to theback-up resource of any one of the primary resources. When this judgedstorage resource corresponds to the back-up resource, the process flowoperation for selecting the back-up resource and for setting the back-upresource shown in FIG. 8 is carried out (step 1111).

In the step 1102, in the case that the storage resource having noresponse corresponds to the primary resource, a confirmation is made asto whether or not there is a response sent from the back-up resource ofthe primary resource (step 1103). When there is no response from theback-up resource (step 1103), such a notification 1109 that the storageresource is brought into an operation down state is transmitted to theclient (step 1110). Even when there is no response from the primaryresource, if a response is issued from the back-up resource (step 1103),the below-mentioned notification 1104 is transmitted to such a clientwhich uses the primary resource via the console 300 (step 1105). Thisnotification 1104 notifies that a storage device is brought into anoperation down state, and also the storage resource is recovered.

Next, in order that the data used by the customer's server 304 can beagain used in the primary resource, the back-up resource is allocated tothe customer's server 304 (step 1106). After this back-up resource hasbeen allocated, a recovery notification 1107 is transmitted to theconsole 300 used by the client by using a client request receptionprogram (WWW server) 500 in a step 1108.

The storage resource operation management method according to this firstembodiment mode of the present invention has been described in the abovedescription.

In the above-described first embodiment mode, with respect to thestorage resource, while not only the resource state information of thestorage resource, but also the logical distance are added as theselection condition, the desirable storage resource is selected. As aresult, even when the performance of the storage resource itself isdeteriorated, such a storage resource having superior access performancefrom the customer's server in total performance may be selected. Also,since the geographical distance of such a storage resource was long,this storage resource could not be entered into the selectable storageresource subjects in the prior art. However, since a logical distance ofthis storage resource is short, this storage resource could be enteredas the selectable storage resource subjects. As a result, the storageresource operation management capable of providing the proper storageresource to the client could be realized among the storage resourceswhich are distributed over the broad range.

Also, while the safety range is set as the disaster influence range withrespect to the storage resource under use, the back-up storage resourcecould be formed with respect to such a storage resource located far fromthe safety distance. As a result, with respect to the disaster such asan earthquake, the storage resource operation management having the highdisaster-resistant performance could be realized.

Next, a description will now be made of a modification with respect tothe above-described embodiment modes.

-   (1). In the above-explained first embodiment, the storage resource    selection condition from the client is defined by that the network    up to the storage resource is the minimum hop count. Also, the    selection condition of the back up resource is defined by that the    back-up resource should be located far from the safety distance.    However, in accordance with the present invention, there is no    limitation in the content of the request, and also in the range.    Alternatively, the range of the request may be defined as follows:    That is, time required for data access operation may be defined    within 1 second; a total hop count between a storage resource and a    node may be selected to be smaller than, or equal to three stages; a    throughput may become higher than, or equal to 50 Mbps; a storage    resource may be installed within 1 Km, and so on.-   (2). In the above-described first embodiment mode, in such a case    that such a storage resource fitted to the selection condition    cannot be founded out as the back-up resource at the distance far    from the safety distance, another storage resource fitted to the    selection condition is newly formed (step 1008).

However, another method may be employed. That is, while the storageresource is not newly formed, another storage resource may be selectedfrom the storage resources present in the SSP, which is located closerthan the safety distance, and is installed at a place separated from theclosest distance from the safety distance.

-   (3). In the above-described first embodiment mode, when the client    uses the storage resource, the customer's server 304 is installed in    the SSP 302, and the client uses this storage resource via the    customer's server 304. Alternatively, while the customer's server is    installed in the client office, this customer's server may be    directly connected to the SAN provided in the SSP so as to use the    storage resource.-   (4). In the first embodiment mode, while both the client request    reception program 500 and the storage management program 502 are    initiated on the management server 303, the database 501 is    constituted. Alternatively, another structure may be employed. That    is, the customer's server 402 may also have the function of the    management server 403 in such a manner that while both the client    request reception program 500 and the storage management program 502    are operable on the customer's server 402, the database 501 is    constructed.-   (5). In the above-described first embodiment mode, the logical    distance acquisition program 401 operated on the customer's server    304 executes the Ping program with respect to the storage so as to    measure both the packet response time and the total hop count    between the customer's server and the storage resource.    Alternatively, this logical distance acquisition program may execute    the Ping program with respect to not only the storage resource but    also the console 300 of the client so as to measure the packet    response time between the console 300 and the storage resource. As    to a logical distance and a geographical distance, a plurality of    nodes and/or a network may be interposed between a node and a    storage resource, or between storage resources. In this alternative    case, the logical distance may express such a total logical distance    defined from the console via the customer's server to the storage    resource.-   (6). In the above-described first embodiment mode, when the logical    distance is acquired, the Ping program is used. However, the present    invention is not limited to such a method for acquiring the logical    distance. Alternatively, other methods may be employed. That is, a    method may be employed by that while data is actually written, or is    actually read with respect to a storage resource, time required to    access data may be acquired. Also, another method may be employed by    that a total hop count up to a storage resource is used, and/or a    throughput of switches provided in a half way of a route is used.-   (7). In the above-described embodiment mode, when the logical    distance between the storage resources is acquired, the    administrator of the SSP 302 manually enters both the latitude and    the longitude of each of the storages from the GUI module 508 of the    storage management program 502 operable on the management server    403. Alternatively, another method may be employed by that such    information (namely, logical distance) used to indicate a    geographical location relationship is entered by designating an    address, or by selecting a point on a map which is commonly owned,    while such latitude and longitude are not used. Also, a further    method may be alternatively employed. That is to say, even in such a    when latitude, longitude, and altitude are used so as to acquire a    logical distance, while a GPS (Global Positioning System) receiver    is additionally mounted on each of the storage resources,    latitude/longitude/altitude of these storage resources may be    acquired from the GPS satellites. In this alternative case, the    management server 303 is required to acquire the respective    longitude/latitude/altitude of all of the storage resources.-   (8). In the above-explained first embodiment mode, with respect to    the new storage source assignment request issued from the client,    the management server 303 selects the optimum storage resource which    can satisfy the requirement of the client, and then, the selected    optimum storage resource to the customer's server 304. However, the    present invention is not limited only to the methods of selecting    and allocating the storage resources. Alternatively, in the case    that the network structure is changed under such a condition that    the storage resource has already been determined with respect to the    customer's server, another method may be employed by judging as to    whether or to the request of the customer's server is satisfied with    respect to the storage resource even after the network structure has    been changed.

FIG. 10 illustratively shows a network structure according to a secondembodiment mode of the present invention, for correcting a storageresource managing method as the above-described method of judging as towhether or not the requirement range can be satisfied as explained inthe above item (8), and for correcting a topology as explained in theabove item (3).

The network structure shown in FIG. 10 is arranged by a customer'sserver 1200, an SSP(A) 1201, and an SSP(B) 1202. Both the SSP(A) 1201and the SSP(B) 1202 represent a branch (A) and another branch (B)contained in a single SSP. While a VPN (Virtual Private Network) isformed on the Internet 1203, both the SSP(A) 1201 and the SSP(B) 1202are connected to this VPN. Although the SSP(A) 1201 and the SSP(B) 1202are installed in different areas, managements of both the SANs 1205 and1206 are carried out in a batch mode by an administrator 1204 of theSSP(B) 1202. The SSP(B) 1202 is arranged by a management server 1204 formanaging storages of the entire SSP, the SAN 1205, and a storage 1206.The SSP(A) 1201 is arranged by an SAN 1207 and a storage 1208. Thecustomer's server 1200 is directly connected to the SAN 1207.

The customer's server 1200 is installed by a client within a firm ofthis client. This customer's server 1200 corresponds to a node used toaccess from the own client to a storage resource of the SSP(B) 1202.Also, this customer's server 1200 may have the same function as aconsole. An arrow 1209 indicates a logical distance between thecustomer's server 1200 and the storage resource 1207 contained in thestorage device 1206. The management server 1204 owns a database 501, andin this management server 1204, both the client request receptionprogram 500 and the storage management program 502 of theabove-explained first embodiment mode shown in FIG. 4 are operated. Thestorage management program 502 owns a movement necessary/unnecessaryjudging module in addition to the processing modules shown in FIG. 3.

In the customer's server 1200, the data access time acquisition program600 shown in FIG. 4 is operated.

While the customer's server 1200 allocates the resources within thestorage 1208 in accordance with the storage resource allocation flowoperation shown in FIG. 5 in the above-described first embodiment mode,this customer's server 1200 uses the allocated resource.

In this second embodiment mode, logical distance information is measuredbased upon a total hop count (namely, total stage number of routers)between the customer's server 1200 and the storage resource. Then, arequirement range of a client is limited to two stages of the hop countwithin the logical distance.

FIG. 11 illustratively shows a network structure in the case that theclient moves in the network structure of FIG. 10, and then, thecustomer's server 1200 is transferred to anther customer's server 1300.The customer's server 1300 shows such a condition that the customer'sserver 1200 shown in FIG. 10 has moved. Both an SSP(A) 1201 and anSSP(B) 1202 are identical to both the SSP(A) 1201 and SSP(B) 1200 shownin FIG. 10. The customer's server 1300 and directly connected to the SAN1205 employed in the SSP(B) 1202. An arrow 1301 represents a logicaldistance (total hop count) between the customer's server 1300 and thestorage resource employed in the storage unit 1208. An arrow 1302indicates a logical distance (total hop count) between the customer'sserver 1300 and the storage device 1206.

FIG. 12 is a flow chart for describing process flow operation forjudging as to whether or not movement of a storage resource is requiredwhen a customer's server moves in the storage management program 502.

In the storage management program 502, in the case that a movementnotification is received from the customer's server 1300 which also ownsthe console, a total hop number defined from the customer's server 1300after has moved up to all of the storage resources (step 1400).

Next, the customer's server 1200 before having moved sets the acquiredhop counts with respect to the storage management program, and then,acquires a requirement range stored in a database, namely a storageresource selection condition (smaller than two hop counts) in a step1401. Next, this acquired hop count is compared with a hop count 1302between the customer's server 1300 after having moved and the storageresource 1208 which has been used having before moved.

After the customer's server 1300 has moved, if the total hop count issmaller than two stages (step 1402), then requirement performance of theclient with respect to the storage resource can be satisfied. As aresult, the storage management program 502 judges that movement of thedata within the storage resource is not required, and then, notifiesthis judgement result to the customer's server 1300 after having moved(step 1403). In the step 1402, in such a case that a total hop number isnot present within the range of the selection condition, a storagedevice whose total hop number is minimum is selected from such storageresources other than the storage device 1208 which has been used by thecustomer's server 1200 (step 1404). Then, the storage management program502 notifies the movement of the data stored within the storage resourceto the customer's server 1300 after having moved (step 1405), and thenthe data stored within the storage resource is actually moved (step1406).

The storage resource management method according to the secondembodiment mode of the present invention has been described in the abovedescription.

In accordance with the above-explained second embodiment, when thegeographical location of the customer's server is moved, if the totalhop count between the customer's server and the storage resource issmaller than the requirement range (within two stages of total hopcount) of the client, then such a judgement is made that the movement ofthe data stored in the storage resource is not required. As aconsequence, reductions in the work cost required for the data movementcan be realized in the storage resource operation movement.

As previously described in detail, in accordance with the presentinvention, in the case that the desirable storage resource is selectedfrom the storage resource groups which are spread in the wide range andthen, the selected storage resource is allocated to the nodes which usethe storage resources, this selection can be carried out by adding thelogical distance to the resource state information stored in thestorage. This resource state information corresponds to the emptycapacity and the use ratio. This logical distance corresponds to theformation related to the data access performance, and the geographicaldistance. As a consequence, even when one storage resource whoseresource state information is inferior than that of another storageresource, since the data access performance via the network becomessuperior, such a storage resource having the best access performance canbe selected by such a node which uses the storage resource. As a result,such a storage network operation can be realized by which such anoptimum storage resource which can be fitted to the requirement rangewith respect to the storage resource can be selected with respect to therequest and can be provided.

Also, with respect to the storage resource which is used by the serverof the client, such a distance (namely, safety distance) is set by whichthe disaster such as an earthquake never gives the adverse influence.Then, the storage resource which is installed at the place separated farfrom the set safety distance is selected, and then, the selected storageresource can be set as the back-up storage resource. Under thiscondition, in the case that the primary storage resource is damaged bysuch local disaster as an earthquake and a flood, the back-up purposestorage resource which is not damaged by the disaster is allocated tothe server of the client by which the data can be maintained. As aconsequence, it is possible to realize such a disaster receivablestorage network managing method.

Furthermore, while the logical distance up to the storage resource isacquired, the requirement range can be acquired. As a result, even insuch a case that the geographical installation position of the server ofthe client which uses the storage resource is moved and thus thedistance between this storage resource and the server is increased, thechange in the logical distances can be measured. As a result, after thegeographical installation location of the server has been moved, it ispossible to judge as to whether or not the logical distance up to thestorage resource is located within the requirement range. Then, when thelogical distance is not varied, it is possible to judge that themovement of the storage resource is not required. As a consequence, thework cost required for the unnecessary movement can be reduced from thestorage network operation management cost.

It will be further understood by those skilled in the art that theforegoing description has been made on embodiments of the invention andthat various changes and modifications may be made in the inventionwithout departing from the spirit of the invention and scope of theappended claims.

1. In a storage network which is arranged by a node for transmitting anaccess request via a network to a storage, a storage group constitutedby at least one storage resource which receives said access request soas to execute a content of the access request, and a management server,said management server comprising: means for acquiring at least one of alogical distance and a geographical distance from at least one of saidnode and said storage resources contained in said storage group, andsaid storage resources contained in said storage group, wherein saidlogical distance is generated based on installation informationregarding installation of each of said node and said storage resources,and wherein said geographical distance is generated based on informationof a physical location of each of said node and said storage resources;means for acquiring from said node a requirement range with respect toat least one of said logical distance and said geographical distance;and means for selecting at least one storage resource for executing theaccess request, issued by said node, from said storage group, while atleast one of said requirement range with respect to said logicaldistance and said requirement range with respect to said geographicaldistance is set as a selecting condition.
 2. A storage resourceoperation managing method in a storage network arranged by a node fortransmitting an access request via a network to a storage and by astorage group constituted by at least one storage resource whichreceives said access request so as to execute a content of the accessrequest, said storage resource operation managing method comprising thesteps of: acquiring at least one of a logical distance and ageographical distance from at least one of said node and said storageresources contained in said storage group, and said storage resourcescontained in said storage group, wherein said logical distance isgenerated based on installation information regarding installation ofeach of said node and said storage resources, and wherein saidgeographical distance is generated based on information of a physicallocation of each of said node and said storage resources; acquiring fromsaid node a requirement range with respect to at least one of saidlogical distance and said geographical distance; and selecting at leastone storage resource for executing the access request, issued by saidnode, from said storage group, while at least one of said requirementrange with respect to said logical distance and said requirement rangewith respect to said geographical distance is set as a selectingcondition, wherein in such a case that the storage resource locatedwithin said requirement range is not present within said storage group,such a storage resource is selected whose at least one of said logicaldistance and said geographical distance is closer than those of anotherstorage resource from said storage group.
 3. A storage resourceoperation managing method in a storage network arranged by a node fortransmitting an access request via a network to a storage and by astorage group constituted by at least one storage resource whichreceives said access request so as to execute a content of the accessrequest, said storage resource operation managing method comprising thesteps of: acquiring at least one of a logical distance and ageographical distance from at least one of said node and said storageresources contained in said storage group, and said storage resourcescontained in said storage group, wherein said logical distance isgenerated based on installation information regarding installation ofeach of said node and said storage resources, and wherein saidgeographical distance is generated based on information of a physicallocation of each of said node and said storage resources; acquiring fromsaid node a requirement range with respect to at least one of saidlogical distance and said geographical distance; and selecting at leastone storage resource for executing the access request, issued by saidnode, from said storage group, while at least one of said requirementrange with respect to said logical distance and said requirement rangewith respect to said geographical distance is set as a selectingcondition, wherein in such a case that the storage resource locatedwithin said requirement range is not present within said storage group,such a storage resource is newly added whose at least one of saidlogical distance and said geographical distance is located within saidrequirement range.
 4. A storage resource operation managing method in astorage network arranged by a node for transmitting an access requestvia a network to a storage and by a storage group constituted by atleast one storage resource which receives said access request so as toexecute a content of the access request, said storage resource operationmanaging method comprising the steps of: acquiring at least one of alogical distance and a geographical distance from at least one of saidnode and said storage resources contained in said storage group, andsaid storage resources contained in said storage group, wherein saidlogical distance is generated based on installation informationregarding installion of each of said node and said storage resource, andwherein said geographical distance is generated based on information ofa physical location of each of said node and said storage resources;acquiring from said node a requirement range with respect to at leastone of said logical distance and said geographical distance; andselecting at least one storage resource for executing the accessrequest, issued by said node, from said storage group, while at leastone of said requirement range with respect to said logical distance andsaid requirement range with respect to said geographical distance is setas a selecting condition.
 5. The storage resource operation managingmethod as claimed in claim 4, wherein as said storage resource selectingcondition, at least one storage resource is selected which is locatedwithin said requirement range of at least one of said logical distanceand said geographical distance.
 6. The storage resource operationmanaging method as claimed in claim 5, wherein within at least onstorage resource located in said requirement range, at least such onestorage resource is selected whose at least one of said logical distanceand said geographical distance is closer than those of other storageresources.
 7. The storage resource operation managing method as claimedin claim 5, wherein within at least one storage resource located in saidrequirement range, at least such one storage resource is selected, thegeographic distance of which is far from the geographical distance ofanother storage resource.
 8. The storage resource operation managingmethod as claimed in claim 4, wherein with respect to at least a firststorage resource contained in said storage group, a requirement rangewith respect to a geographical distance from said first storage resourceis acquired; a second storage resource is selected from said storagegroup located within the requirement range with respect to saidgeographical distance from said first storage resource, or a secondstorage within the requirement range with respect to said geographicaldistance from said first storage resource; copied data as to at least adata portion of such data stored in said first storage resource isstored into said second storage resource; and in the case that anoccurrence of a trouble of said first storage resource is detected, theaccess request issued from said node, which is transmitted to said firststorage resource, is executed with respect to said copied data of thedata stored in said second storage resource.
 9. The storage resourceoperation managing method as claimed in claim 4, further comprising thesteps of: in such a case that a geographical location of said node ischanged from a first setting position to a second setting positionjudging whether or not a logical distance defined from said node set atthe second setting position up to such a storage resource which executesan access request transmitted by said node is located within saidrequirement range; and moving data in said storage resource into anotherstorage resource, when the logical distance from said second settingposition is located is beyond said requirement range.
 10. In a networksystem including a plurality of storage resources and at least one ofcomputers being coupled to said storage devices via a network for usingdata stored in said storage resource, a storage resource managing methodcomprising the steps of: acquiring storage resource informationincluding at least one of a logical distance and a geographical distancebetween at least one of said computers and each of said storageresources, wherein said logical distance is generated based oninstallation information regarding installation of each of said node andsaid storage resources, and wherein said geographical distance isgenerated based on information of a physical location of each of saidnode and said storage resources; acquiring an allocation request forassigning storage resource to said computer based on a requirement rangewith respect to at least one of said logical distance and saidgeographical distance; and allocating, to said computer, a storageresource corresponding to said acquired storage resource information andsaid requirement range included in said allocation request storageresource.
 11. The storage resource managing method according to claim10, wherein the step of allocating comprises the step of: if the storageresource located within said requirement range is not present,allocating at least one storage resource that does not satisfy saidrequirement range based on the acquired storage resource information.12. The storage resource managing method according to claim 11, whereinthe allocated at least one storage resource that does not satisfy saidrequirement range is a storage resource wherein a difference betweeninformation regarding a storage device forming the allocated at leastone storage resource and said requirement range is smaller than adifference between information regarding devices forming other storageresources that do not satisfy said requirement range.
 13. The storageresource managing method according to claim 11, wherein at least one ofsaid logical distance and said geographical distance of the allocated atleast one storage resource is closer than those of the other storagedevise -resource that does not satisfy said requirement range.
 14. Thestorage resource managing method according to claim 11, wherein at leastone of said logical distance and said geographical distance of theallocated at least one storage resource is farther than those of theother storage devise -resource that do not satisfy said requirementrange.
 15. The storage resource managing method according to claim 11,wherein the step of allocating comprises the step of: if the storageresource located within said requirement range is not present, adding atleast one of new storage resources that satisfy said requirement rangeand allocating at least one of said new storage resources.
 16. Thestorage resource managing method according to claim 10, furthercomprising the steps of: if a geographical location of said computer ischanged from a first location to a second location, judging whether ornot a logical distance between said computer in said second location andsaid allocated storage resource is within said requirement range; ifsaid logical distance between said computer is said second location andsaid allocated storage resource is beyond said requirement range, addinga storage resource that satisfies said requirement range; and movingdata to the added storage resource.
 17. The storage resource operationmanaging method according to claim 4, wherein said installationinformation includes an operation ratio, a storage capacity, a rotationper minute of disk, an access time in disk, a packet response time, anda hop number.
 18. The storage resource operation managing methodaccording to claim 4, wherein said information of said geographicaldistance is based on a latitude and a longitude of each of said node andstorage resources.